RFR: 8299974: Replace NULL with nullptr in share/adlc/

[Vladimir Kozlov]

On Tue, 16 May 2023 11:54:20 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

> Hi, this PR changes all occurrences of NULL to nullptr for the subdirectory share/adlc. Unfortunately the script that does the change isn't perfect, and so we need to comb through these manually to make sure nothing has gone wrong. I also review these changes but things slip past my eyes sometimes.
> 
> Here are some typical things to look out for:
> 
> 1. No changes but copyright header changed (probably because I reverted some changes but forgot the copyright).
> 2. Macros having their NULL changed to nullptr, these are added to the script when I find them. They should be NULL.
> 3. nullptr in comments and logs. We try to use lower case "null" in these cases as it reads better. An exception is made when code expressions are in a comment.
> 
> An example of this:
> 
> ```c++
> // This function returns null
> void* ret_null();
> // This function returns true if *x == nullptr
> bool is_nullptr(void** x);
> 
> 
> Note how `nullptr` participates in a code expression here, we really are talking about the specific value `nullptr`.
> 
> Thanks!

I have few comments

src/hotspot/share/adlc/adlparse.cpp line 4595:

> 4593: 
> 4594:   if( _curline == nullptr )          // Return null at EOF.
> 4595:     return nullptr;

Spacing of comment. Please, fix code style to:

  if (_curline == nullptr) {         // Return null at EOF.
    return nullptr;
  }

src/hotspot/share/adlc/adlparse.cpp line 4627:

> 4625: 
> 4626:   // Make sure we do not try to use #defined identifiers.  If start is
> 4627:   // null an error was already reported.

May be use `nullptr` here since we are talking about value in `start` variable.

src/hotspot/share/adlc/adlparse.cpp line 4795:

> 4793: 
> 4794:   if( _curline == nullptr )       // Return null at EOF.
> 4795:     return 0;

Code style.

src/hotspot/share/adlc/adlparse.cpp line 4830:

> 4828: 
> 4829:   if( _curline == nullptr )       // Return null at EOF.
> 4830:     return  nullptr;

Code style.

src/hotspot/share/adlc/adlparse.cpp line 5242:

> 5240:   }
> 5241:   if( _curline != nullptr )         // at end of file _curchar isn't valid
> 5242:     _curchar = *_ptr;               // reset _curchar to maintain invariant

Code style.

-------------

PR Review: https://git.openjdk.org/jdk/pull/14008#pullrequestreview-1442573130
PR Review Comment: https://git.openjdk.org/jdk/pull/14008#discussion_r1204642438
PR Review Comment: https://git.openjdk.org/jdk/pull/14008#discussion_r1204644334
PR Review Comment: https://git.openjdk.org/jdk/pull/14008#discussion_r1204645287
PR Review Comment: https://git.openjdk.org/jdk/pull/14008#discussion_r1204645560
PR Review Comment: https://git.openjdk.org/jdk/pull/14008#discussion_r1204646229